Recognition of all too common occurrences of sickness which sometimes prove fatal due to diseases transmitted by inadvertent needle sticks has resulted in development of a variety of safety catheter needle devices which are used in the areas of I.V. catheters. Such devices comprise devices which utilize distally displaced shields which are projected over a retracted needle following insertion of a catheter and other devices which automatically retract the needle when activated by a button push. Other possibilities for catheter insertion needle safety devices include those devices which blunt the needle following catheter insertion.
Even though safety catheter devices have been in commerce for years, less than half the catheters sold in the United States are safety catheters. The most likely reason for sales of safety catheters remaining in the minority is unit cost. Currently, safety catheters sell for about twice the cost of non-safety catheters. As non-safety catheter use represents a significant source of contaminated needle sticks, one might conclude that a safety catheter which could be fabricated for a cost which is competitive with non-safety catheters would find more ready acceptance in the marketplace than current safety catheters, achieve a greater market share and thereby provide significant value through reduction of inadvertent contaminated needle sticks.
As it is generally considered prudent to leave one hand free to care for a patient, particularly to a wound site from which a needle is being withdrawn, a natural consequence is a need for devices which are operable by a single hand. For this reason, devices which can be operated by a single hand or digit thereof are most often preferred over devices requiring more. Further, ease of manipulating the needle from an inserted position to a retracted position is an important characteristic of a safety device requiring critical attention in conception and design. However, even though manipulation should be easy, needle retraction must not be inadvertent. As a consequence, a preferred device would likely be one which requires a positive action to change a state of a retraction mechanism from one stable state to another when the needle is retracted.